JPH1175687A - Production of soybean milk fermentation food product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject product that has good taste with reduction in the formation of acetic acid and in the change of the acidity during the storage by inoculating soybean milk with a microorganism in Bifidobacterium to effect fermentation, stopping the fermentation at a specific time and adding a specific organic acid to the fermentation system. SOLUTION: Soybean milk is inoculated with a microorganism in Bifidobacterium, for example, Bifidobacterium breve, to effect fermentation. Then, at the stage that the amount of the acetic acid formed is still permissible in its taste, preferably at the stage that the concentration of the acetic acid reaches <=30 mM, the fermentation is discontinued. Then, an organic acid other than acetic acid that can be acceptable as food products (for example, citric acid or lactic acid) is added thereby adjusting the pH of the fermentation product to 3.5-5. The stage that the formation of acetic acid is in the permissible range in taste can be judged when the pH of the fermentation mixture reaches 5.5-5. In a preferred embodiment, the fermentation is continued until the number of the viable cell bodies of the microorganism in Bifidobacterium increases to 1×10<8> cells/ml.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a fermented soymilk food using a microorganism of the genus Bifidobacterium, particularly a method for producing a fermented soymilk food having a small acidity change during storage and a fermented soymilk food having a good flavor obtained thereby. It is about.

[0002]

2. Description of the Related Art Many fermentation treatments with microorganisms have been practiced for the purpose of organoleptically improving soy milk having a soybean smell or bluish taste. The types of microorganisms used in these fermentation treatments are diversified, such as lactic acid bacteria, yeast, natto bacteria, acetic acid bacteria, and koji molds. I have.

[0003] Among such microorganisms, Bifidobacterium microorganisms metabolize sugar. In addition, it is already known that soymilk has a growth-promoting action of a microorganism of the genus Bifidobacterium, for example, because soymilk contains soybean oligosaccharides (Yoichi Kobayashi et al., P. 96, 1984).
Intestinal Flora and Food Factors, Academic Publishing Center). Therefore, it is preferable to use Bifidobacterium microorganisms in the production of fermented soymilk foods.

There have been many research reports on the usefulness of Bifidobacterium microorganisms. For example,
It has been shown that the administration of a live bacterial preparation of Bifidobacterium genus microorganism (Bifidobacterium breve) has a curative effect on intractable diarrhea in children, and the mechanism of action is considered to improve the intestinal flora. I have. Further, for example, it has been clarified that a decrease in fecal putrefaction products and a decrease in putrefaction product-producing bacteria are observed by administration to an adult, and furthermore, an immunostimulatory effect of a Bifidobacterium microorganism. Thus, Bifidobacterium microorganisms are thought to contribute to human health through improvement of the intestinal environment (edited by Tomohari Mitsuoka, Bifidobacterium research, 1994).
Year). For this reason, while various products using Bifidobacterium genus microorganisms are being developed, the amount of Bifidobacterium genus microorganisms in fermented soy milk is at least 1 × 10
It is required to contain more than ⁷ cells / ml.

[0005]

However, the microorganisms belonging to the genus Bifidobacterium metabolize sugar to produce lactic acid and acetic acid at a molar ratio of 1: 1.5, respectively. Drops. In addition, acetic acid generated here is an irritating acid and causes a reduction in the flavor of fermented soymilk.

In order to suppress the production of acetic acid, it is conceivable to stop the fermentation at an early stage, but it is difficult to stop the fermentation while keeping the viable cell count at or above a certain level. Even if the fermentation is temporarily stopped at a high pH level, for example, by cooling, etc., it is not possible to completely suppress acetic acid production, and a decrease in pH and flavor during production and storage is inevitable. .

Accordingly, an object of the present invention is to provide a bifidactact
The number of viable bacteria of the genus Lium is 1 × 10 ⁷Keep at least cell / ml
In addition, acidity changes during storage are small, and acetic acid generation is suppressed
To provide a method for producing a fermented soy milk food having a favorable flavor.
And there.

[0008]

Means for Solving the Problems In view of this situation, the present inventors have conducted intensive studies. As a result, the addition of a specific organic acid at a certain stage of fermentation stabilizes the acidity and improves the flavor. The present inventors have found that fermented soymilk foods can be obtained and completed the present invention.

That is, the present invention relates to a method for producing a fermented soymilk food by inoculating a soymilk with a microorganism of the genus Bifidobacterium, and fermenting the fermented food at a stage where the amount of acetic acid produced in the fermented product is flavorably acceptable. After the suspension, a method for producing a fermented soymilk food product characterized by adjusting the pH of the fermented product by adding an organic acid other than acetic acid which is acceptable as a food, and a fermented soymilk food product obtained by the production method are provided. Things.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The soymilk used as a raw material in the present invention is preferably a raw material such as whole soybean, defatted soybean, or flaked soybean containing oil and fat. Good. Normally, soy milk is immersed in water and then ground with hot water or hot water containing 0.5 to 1.0% by weight of sodium carbonate (hereinafter simply referred to as%). The soymilk used in the present invention may be produced by any method.

[0011] In addition, soymilk has a sugar used in foods such as sucrose, glucose, fructose, invert sugar and the like; and is necessary for the growth of microorganisms such as meat extract, peptone, yeast extract and peptide for subsequent microbial treatment. Nutrients may be added.

In the present invention, one or more microorganisms of the genus Bifidobacterium are inoculated to these soy milks, and fermentation is performed until the acetic acid content in the soy milk can be tolerated.

The microorganism of the genus Bifidobacterium to be inoculated into soy milk is not particularly limited, and various microorganisms can be used. For example, Bifidobacterium breve,
Bifidobacterium longum, Bifidobacterium infantis, Bifidobacterium addressentis, Bifidobacterium bifidum, Bifidobacterium angularum, Bifidobacterium catenulatum, etc. However, it is desirable to select a medium having such a property that the acetic acid concentration in the medium becomes 70 mM or less when cultured in a soymilk medium to at least 1 × 10 ⁷ cells / ml.

The fermentation method is not particularly limited as long as it is carried out under normal fermentation conditions. For example, after inoculating the cultured soybean milk of the microorganism of the genus Bifidobacterium into the soybean milk,
Fermentation may be carried out by appropriately determining conditions such as temperature, time, stirring, and anaerobic bacterium suitable for the microorganism. Fermentation can be performed under conditions suitable for culture, for example, static culture, stirring culture, shaking culture, and aeration culture.

The fermentation may be a mixed fermentation in which a plurality of strains of a microorganism of the genus Bifidobacterium are combined, or a continuous fermentation in which a plurality of strains are combined.
Further, a mixed fermentation with a microorganism other than a Bifidobacterium microorganism may be used.

Examples of such microorganisms include bacteria such as Lactobacillus, Lactococcus, Streptococcus, Leuconostoc, Bacillus, Acetobacter, Gluconobacter and the like, or Saccharomyces and Candida. , Yeasts such as Rhodotorula, Pichia, Schizosaccharomyces, Torula, Tygosaccharomyces, etc. Can be mentioned.

In the fermentation, the viable cell count of the microorganism belonging to the genus Bifidobacterium is 1 × 10 ⁷ cells / ml or more, preferably 1 × 10 ⁸ cells / ml.
It is preferable to perform the treatment until the cell concentration reaches cell / ml in order to exhibit various effects of the microorganism.

In the present invention, the fermentation needs to be stopped at a stage where the amount of acetic acid produced can be taste-acceptable. The stage at which the acetic acid content is acceptable is determined in consideration of other flavor materials added to the final product as needed, and the acetic acid concentration in the fermented product is 70 mM, preferably 50 mM.
Desirably, it is at a stage where the concentration becomes mM, more preferably 30 mM or less. In addition, this step is performed at pH 4.5 or higher, preferably in the range of pH 4.5 to 6.0, and more preferably in the range of pH 5.5 to 5.5.
It can also be determined from 5.0.

The fermentation can be stopped by cooling.

In the present invention, after the fermentation is stopped, the pH is adjusted with an organic acid. The organic acid used here is not particularly limited as long as it is an acid acceptable as food other than acetic acid, but preferably, citric acid, lactic acid, malic acid, ascorbic acid,
Tartaric acid, gluconic acid, succinic acid, glutamic acid and the like can be used. The pH to be adjusted may be determined according to the stable pH of the microorganism of the genus Bifidobacterium to be used, and may be lowered by about 0.1 to 2.5 from the pH at which the fermentation is stopped, and the final fermented soymilk food It is desirable to adjust the pH of the solution to 3.5 to 5.0.

[0021] The fermented soymilk food product, which has been adjusted in pH, can be added with various sugars, stabilizers, fragrances and the like, if necessary, in the same manner as general fermented food products. Further, the fermented soymilk of the present invention can be processed into various shapes, and may be in a liquid, paste, sponge, or solid state. Further, the foods are not limited to soy milk drinks, and include various foods such as soy milk yogurt, soy milk pudding, and tofu.

[0022]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1 Soy milk (manufactured by Shikoku Kakoki Co., Ltd., solid content 12.0%, crude fat 2.4)
(8%, 4.71% crude protein) was steam-sterilized at 100 ° C. for 90 minutes to sterile soymilk, and Bifidobacterium breve previously subcultured with anaerobic soymilk for several generations.
YIT 4065 (FERM P-15488) to 0.
3% was inoculated and cultured at 34 ° C., fermentation was stopped by cooling at pH 5.3, and a fermented product of soymilk was produced. Viable bacteria count is 2 × 1
It was ⁹ cells / ml. Add lactic acid to this fermented product and add
After adjusting to 4.6, a fructose-fructose solution (5%) was added to produce a fermented soymilk food, and the acidity change when stored in an anaerobic state at 10 ° C was measured. Controls without addition of acid were used as controls. The results are shown in FIG.

The fermented soymilk food to which the lactic acid of the present invention has been added comprises:
Almost no change in acidity after storage for 14 days,
The storage stability of the product was good. On the other hand, the control product in which the acidity was not adjusted with lactic acid increased the acidity by a factor of two or more, and the storage stability of the product was extremely poor.

Example 2 Soy milk (manufactured by Shikoku Kakoki Co., Ltd., solid content 12.0%, crude fat 2.4)
(8%, crude protein 4.71%) was sterilized by steam at 100 ° C. for 90 minutes and sterilized soymilk was prepared by subcultured several times with anaerobic soymilk.
4065 (FERM P-15488) was inoculated at 0.5%, cultured at 34 ° C, and fermentation was stopped by cooling at pH 5.0 to produce a fermented product of soymilk. The viable cell count of the obtained fermented product was 2 × 10 ⁹ cells / ml. After adding citric acid to the fermented soymilk to adjust the pH to 4.6, 7% of sucrose was added to produce a fermented soymilk-added soybean food. Further, pineapple fruit is added to a final concentration of 3%, tamarillo fruit is added to a final concentration of 3%, or carrot juice is added to a final concentration of 0.01%.
% Or matcha in a final concentration of 0.02
% To produce fermented soymilk foods of various flavors. Six kinds of samples including the sample (pH 5.0) of which pH was not adjusted by acid were measured at 10 ° C under anaerobic condition, and the change in acidity was measured. Was done. FIG. 2 shows the measurement results of the acidity change.

The pH-adjusted sample showed almost no change in the acidity even after storage for 14 days, indicating that the product had good storage stability. On the other hand, in the sample without pH adjustment, the acidity greatly increased during storage, and the storage stability of the product was poor. In addition, in the sensory evaluation, any of the samples subjected to pH adjustment hardly felt any odor of acetic acid, and was evaluated to have a favorable flavor. On the other hand, samples without pH adjustment
It was evaluated that an acetic acid smell was felt.

[0027]

According to the method for producing a fermented soymilk food of the present invention, the content of acetic acid which deteriorates the flavor can be suppressed, so that a fermented soymilk food produced by a microorganism of the genus Bifidobacterium having a good flavor can be produced. In addition, by adjusting the product pH to a state where the microorganism of the genus Bifidobacterium is stabilized with an organic acid, it is possible to produce a fermented soymilk food product in which the acidity change during storage is extremely small.

[Brief description of the drawings]

FIG. 1 is a graph showing a change in acidity during storage of a fermented soybean milk.

FIG. 2 is a diagram showing a change in acidity during storage of a fermented soymilk.

Claims (5)

[Claims] 1. A method for producing a fermented soybean milk product by inoculating a soymilk with a microorganism belonging to the genus Bifidobacterium and fermenting the soymilk fermented food, after stopping the fermentation at a stage where the amount of acetic acid produced in the fermented product is flavorably acceptable. A method for producing a fermented soymilk food, comprising adjusting the pH of a fermented product by adding an organic acid other than acetic acid which is acceptable as a food. 2. The production method according to claim 1, wherein the stage in which the amount of acetic acid produced in the fermented product is acceptable in terms of flavor is a stage in which the acetic acid concentration of the fermented product is 70 mM or less. 3. The production method according to claim 1, wherein the stage in which the amount of acetic acid produced in the fermented product is taste-acceptable is a stage in which the pH of the fermented product is 4.5 or more. 4. The method according to claim 1, wherein the pH of the fermented product is adjusted to a range of 3.5 to 5.0. 5. The organic acid other than acetic acid, which is acceptable as a food, is one or more selected from citric acid, lactic acid, malic acid, ascorbic acid, tartaric acid, gluconic acid, succinic acid, and glutamic acid. 5. The production method according to any one of items 4 to 4.